Setting the screen/console size in an applet

Hello, I was hoping someone could help me out. I'm working with the ACM Library and I want to set the size of the window that opens up. To a size like 800x600. I can't seem to find any method that will allow me to set this size so I don't have to resize the window everytime I run my programs.

Anyone know how this can be done? Sorry if this is a stupid question, I'm a noob afterall!